Here are the most conservative and liberal towns in America, according to one key measurement

Crowdpac, a company working toward more transparency and widespread participation in campaign finance, used decades of campaign-finance reports from the Federal Election Commission to find out how liberal or conservative various donors are.

Liberal donors will donate to liberal candidates; conservatives running for office will seek out conservative donors. By tracking the relationships between donors and candidates, Crowdpac was able to assign an ideology score to candidates and donors alike.